Is there any reason the water can’t be safely consumed later? It’s not toxic or nuclear is it? The cooling water didn’t just up and disappear did it?
Edit: Links provided in the comments…
- https://arxiv.org/pdf/2304.03271
- https://www.youtube.com/watch?v=H_c6MWk7PQc
- https://www.youtube.com/watch?v=H_c6MWk7PQc&t=1264
- https://pivot-to-ai.com/2026/03/06/how-much-water-do-the-data-centres-use-its-a-secret/
- https://ui.adsabs.harvard.edu/abs/2025EcInd.17012986J/abstract
- https://en.wikipedia.org/wiki/List_of_tallest_cooling_towers
- https://en.wikipedia.org/wiki/Niederaussem_Power_Station
Notable comments:
- https://lemmy.world/comment/23672269
- https://sh.itjust.works/comment/25288634
- https://lemmy.cafe/comment/16350045
- https://sh.itjust.works/comment/25294655
Edit addendum: I’d like to thank everyone that’s participated in this question thread, sorry if I missed any good relevant links in the comments.
To be clear, I still loathe the whole AI datacenter era, it really is heavily wasteful of resources, notably energy, but I wanted to better understand the water usage situation.


Further to this, as well as the source of the water often being the local city’s drinking water supply (as we’ve found this puts a strain on that supply), evaporative cooling systems concentrate the minerals / contaminants in the water, meaning a smaller (relative to what is evaporated) of now highly-concentrated runoff water also has to be constantly disposed of. This likely is also going into the city’s wastewater systems.
Radiators for closed-loop systems do also occupy more space (for the same cooling capacity) versus evaporative cooling towers, and are more limited in the range of climates they can be deployed in.
On balance though, the closed-loop cooling should always be the first choice; if it works for the deployment it will never be the wrong choice on a long-term / total cost of ownership basis.